A sequential optimization strategy, based on statistical experimental designs was employed to enhance Aspergillus awamori EM66 exochitinase productivity. First, a 2-level Plackett–Burman design was applied to differentiate between the bioprocess parameters, which significantly influence exochitinase production. The second optimization step was performed using central composite design (CCD), in order to optimize variables amounts that have the highest positive significant effect on exochitinase production. A maximal activity (5998mU/ml) for exochitinase reported approximately 22 fold increase compared to the basal medium activity. Mortality 92%, 86.67% and 65.67% was recorded when the partial pure fungal exochitinase was applied to the diet of the greater wax moth larvae, Galleria mellonella, , the cotton leaf worm, Spodoptera littoralis, and the black cutworm, Agrotis ipsilon, respectively. The results indicated to the importance of Aspergillus awamori EM66 exochitinase as an effective biopesticide.
Key words: Aspergillus awamori; Bio pesticides; Central composite design; Exochitinase
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